Identification of L-Methionine-S-Sulfoximine as the Convulsant Isomer of Methionine Sulfoximine

Inhibition of glutamine synthetase by methionine sulfoximine. Studies on methionine sulfoximine phosphate.

The irreversible inhibition of glutamine synthetase by methionine sulfoximine is associated with the tight binding to the enzyme of adenosine diphosphate and methionine sulfoximine phosphate; the latter compound can be cleaved nonenzymatically and also by phosphatases to equimolar amounts of methionine sulfoximine and inorganic phosphate. Methionine sulfoximine phosphate is oxidized by L-amino ...

Effect of the convulsant methionine sulfoximine on the in vivo uptake and metabolism of D-methionine in rat brain.

D-methionine was administered intraperitoneally to rats in tracer (22.5 pmoles/kg) and large doses (4.7 mmoles/kg) and the brain levels of total (D + L) methionine, as well as of cysteine (+cystine) and glutathione were determined. The effect of co-administering the convulsant agent, L-methionine-DL-sulfoximine (MSO) was also examined. The administration of tracer doses of Cl2-D-methionine resu...

The inhibition of cerebral glutamine synthetase by structural analogs of the convulsant dl-methionine sulfoximine.

GLUTAMINE synthetase [L-glutamate-ammonia ligase (ADP)] (EC 6.3.1.2) of rat cerebral cortex may be readily inhibited by the convulsant agent dl-methionine-di-sulfoximine (MSO), both in vitro and in vivo. 1, 8 Although in vitro this inhibition is readily reversible by excess substrate, L-glutamate, the inhibition in vivo appears to reflect a nonreversible interaction of the convulsant drug with ...

L-methionine sulfoximine as a novel selection agent for genetic transformation of orchids.

A key challenge in molecular breeding of orchids is the creation of efficient and reproducible gene transformation systems. In this study, we report a new transformation method utilizing L-methionine sulfoximine (MSO) as a novel agent for selection of transgenic Dendrobium hybrids D. Madame Thong-In and D. Chao Praya Smile with the bialaphos resistance (bar) gene as a selectable marker. Gene tr...

Binding enthalpies for glutamine synthetase interactions with L-S- and L-R-diastereoisomers of the substrate analog L-methionine sulfoximine.